I am running Tomcat 6.0, Eclipse, Spring 3, Hibernate 3, MySQL 5.1 on my Windows7 Ultimate. I tried cleaning everything and I tried deleting the server and re-add, it didn't help. In fact, I got this error only after I did a "clean..." on Tomcat. "clean...." did re-publish all the projects for me.

I encountered this problem before. No matter what I did, no effect. Finally, I had to recreate a whole new Eclipse project (with different name) to get around it. Now, again....

This code ran fine on other non-Windows 7 OS. I ran out of to blame....could Windows 7 Ultimate has something to do with it? How can I make it work again?

It's a little late, and you did not specified it on your post, but if you are using maven plugin perhaps I can help...

I had a hard time to make it work, but thanks to "Alexander Pogrebnyak" I was able to make Eclipse Web Projects work with Maven through m2e:

Before starting, I must say that I'm a very suspicious man, so I always start by cleaning all my projects using "Eclipse -> Project -> Clean..." menu (without "start a build immediately" option checked). I also do not have "Eclipse -> Project -> Build Automatically" option checked.

By the way, I suppose that you will have your m2e plugin installed already, or what I'm going to state has no meaning...

Well, let's start:

**First, bye bye Server configuration:**

1) If your have any project in a previous server configuration, remove it (right click on the server and select "Add and remove" option)

1) Deploy and run your web application (Right click your web project, "Pop up Menu -> Run As -> Run on Server")

2) You will be asked to create another server configuration. It will create the "Servers" project/folder again, but that's the way it is.

That's it!!! I gotta admit, once I ran the server, it didn't work, but this time (i dunnot know why) "Log4J" libraries could not be found. After one "project clean" + "maven clean" and one "maven install" + "project build" another message stating that my Servlet class could not be found. Once again, I executed a "project clean" + "maven clean" and a "maven install" + "project build" and "voila"!!! It worked (And that's why I'm so suspicious).

I was starting to get worried with this new Juno + m2e double... Never had this kind of problem with Indigo or Ganymede... But I guess I can trust Eclipse again (can I?)

It's a typo (either here or in your server.xml) that your attribute values have extraneous spaces, right? Otherwise, please elaborate on what was included when you "tried all suggestions from all corners of the numerous development communities but to no avail."